The Four Hour Stack: Every Tool Running My Business While I Rest
The system I built when I had no time, no energy, and a mortgage to pay
I want to tell you something about fatigue that most people get wrong.
Tiredness affects your eyes. Fatigue is in your bones. It doesn’t negotiate. It doesn’t respond to willpower or caffeine or the size of your mortgage. When it arrives, your body stops. That’s it.
I know this because, after my stroke, fatigue became the fixed constraint around which I had to rebuild everything.
Here’s the situation I was in: I’d had a stroke. I’d also just been made redundant almost immediately after I came home.
The mortgage wasn’t going to wait. So I did what most people would do - I tried to push through. I sat at my desk and worked.
For four hours, that worked. Then my body made the decision for me.
I couldn’t focus. I couldn’t think straight. The fatigue had arrived and there was nothing to be done about it except stop.
That moment clarified something I doubt I would have learned any other way: I had to work smarter. Not as a philosophy. As a practical necessity.
Most writing about productivity comes from people who chose to work differently. They ran an experiment, it worked out, they wrote about it.
That’s not what happened here.
The constraint came first. The system came second. And because the constraint wasn’t optional, neither was the quality of the system.
Every tool I use had to earn its place. The ones that didn’t were cut.
The first thing that actually helped was AI: ChatGPT initially. Then Perplexity. Maybe now Claude.
What AI gave me wasn’t productivity in the abstract sense. It gave me the ability to do a full day’s work in the four hours my body would allow. That distinction matters. It wasn’t about doing more. It was about not falling behind.
But AI on its own isn’t a system. It needs a structure around it.
Here’s mine.
How an Idea Becomes a Piece of Work
Everything starts with Readwise.
I read a lot - articles, books, newsletters. When something is worth keeping, I highlight it. That highlight goes into Readwise, where it joins everything else I’ve found useful. Readwise surfaces things back at the right moment and connects ideas across sources. It turns reading from a passive habit into something that compounds.
When a highlight sparks an idea, I capture a rough note in Tana — my current thinking layer, which I’m evaluating as a replacement for Obsidian. The note might be a sentence. Sometimes a paragraph. Then I leave it for a week.
This is the most important part of the system.
About 80% of ideas that feel valuable on Monday feel hollow by the following Monday. The urgency fades. The insight turns out to be obvious or already covered or simply not worth four hours of limited energy. Those ideas get discarded before they ever reach Tana. I’ve stopped treating that as failure — it’s a filter, not a flaw. The PKM stays clean because the noise never gets in.
The 20% that survive the week earn their place in Tana, where they develop into something worth writing.
Those move into iA Writer. No formatting options. No distractions. Just the writing. For someone working to a tight time constraint, a tool that does one thing well is more useful than a tool that does many things adequately.
For ideas that arrive away from my desk - a thought from a podcast, something from an audiobook - I use Drafts to record a quick voice note. It waits until I’m ready for it.
Finished work goes into DEVONthink, alongside everything else: contracts, invoices, client files, health records. All of it searchable in seconds from my Mac or my phone.
That’s the full process. Readwise to Tana to iA Writer to DEVONthink, with AI as the thinking layer running alongside all of it.
The Stack
Readwise captures and surfaces everything I read. I’m an affiliate — I wouldn’t be if I wasn’t reliant on it - and that’s an affiliate link (but it does get you twice the standard free trial length to go along with the warm, fuzzy feeling that you’re helping an internet stranger out!).
The difference between reading that evaporates and reading that compounds is, for me, Readwise. I wouldn’t be able to write consistently without it.
Tana is where ideas develop. I’m still evaluating it, but the integration between thinking and working is tighter here than anywhere else I’ve tried.
iA Writer is where the writing happens. Single-purpose, distraction-free. That’s the point.
TickTick is my task management tool - the thing that tells me what to do when I sit down at 8am and 2pm. Personal and business tasks, broken down by project and client, planned daily and weekly.
With only four hours available, knowing exactly what needs to happen before I open my laptop isn’t optional. It integrates with Notion, which means my task list and my business performance tracking stay connected without manual effort.
DEVONthink stores everything. It’s not a beautiful tool. It doesn’t need to be. It’s reliable, it’s searchable, and it works the same way every time. When your hours are limited, reliability matters more than elegance. Also something I’d genuinely miss.
Claude is the most recent addition that I’m evaluating. What makes it useful for my situation specifically isn’t just the quality of the output - it’s that it can work when I’m not working. A task briefed at 8am can be done by 2pm while I’m resting. For a business that runs in two two-hour blocks, that changes the shape of the day.
Notion tracks business performance. I use it lightly and deliberately - not as a second brain or project management system, but specifically for measuring what matters, as the likes of Tana and Obsidian can’t handle maths at the moment.
Revenue, targets, progress. It handles simple calculations cleanly and gives me a clear picture of where the business stands without overcomplicating it. One tool, one job.
Canva handles everything visual. I’m not a designer - I’ll be honest about that. But Canva means that doesn’t matter. Social graphics, client-facing documents, presentation materials - all of it looks professional without me needing skills I don’t have.
For a solopreneur, that gap between what you can make and what looks credible is a real problem. Canva solves it for me.
Drafts catches ideas when I’m away from my desk. Voice notes that sit and wait. Simple and reliable.
The Question Worth Asking
You don’t need my constraints to find this useful.
But there’s a question underneath all of this that applies regardless of your situation:
If every tool in your stack had to justify its place, what would survive?
Most people don’t ask it until they have to. I’d recommend asking it before then.
The stack isn’t the answer. The question is.
Four Hour Freedom is a newsletter about building sustainable work around your life. If this was useful , I’d love it if you subscribed to the newsletter.
Failing that, you can Buy me a coffee (I hugely appreciate it!) or follow me socially on: Bluesky | Substack | Instagram
The Readwise and DEVONthink links above are affiliate links - you get a trial (an extended one with Readwise!), I get a small commission if you stay. I only recommend tools I use every day - and they both rock. Honestly!